Seat scaffold

ABSTRACT

A scaffold suspended from a single cable and having an operatorsupporting area substantially spaced rearwardly from its forward side, a cable guide means attached to an upper part of the frame of the scaffold and disposed a substantial and preferably adjustable distance from a forward side of the frame and toward a position above the position of the operator, whereby the downward force of the weight of the operator is partially counterbalanced, wheel means on the forward side of the frame and below the operator&#39;&#39;s position for engaging the outer surface of a building so as to counteract the remainder of the downward force of the operator on the frame, the wheels being adjustably positionable greater and lesser distances to the right and left of the frame respectively, a winch on the frame attaching the cable.

United States Patent I Primary Examiner Reinaldo P. Machado Atmrneyl-liram A. Sturges ABSTRACT: A scaffold suspended from a single cable and having an operator-supporting area substantially spaced rearwardly from its forward side, a cable guide means attached to an upper part of the frame of the scaffold and disposed a substantial and preferably adjustable distance from a forward side of the frame and toward a position above the position of the operator, whereby the downward force of the weight of the operator is partially counterbalanced, wheel means on the forward side of the frame and below the operator's position for engaging the outer surface ofa building so as to counteract the remainder of the downward force of the operator on the frame, the wheels being adjustably positionable greater and lesser distances to the right and left of the frame respectively, a winch on the frame attaching the cable.

SEAT SCAFFOLD FIELD OF THE INVENTION This invention is in the field of scaffolds adapted to be used during work on the outer sides of buildings and other structures, which latter have side surfaces adapted to be engaged by wheels for holding the scaffold in the desired position.

More specifically, the scaffold of this invention is in the field of scaffolds adapted to be operated by one man and suspended from a single cable.

DESCRIPTION OF THE PRIOR ART In the prior art, scaffolds in this field have been extremely unstable. For the most part, they have been simply chairs to which a block and tackle can be attached wherein the operator has the necessity of somehow preventing his twisting around sideways and backwards with respect to his work by constant attention to the engagement of the wall of the building with his feet.

With such devices, the closer the scaffold is to the upper anchoring point of its cable, the more difficult it is for the operator to hold the scaffold far enough out from the building for freedom of action while doing the work.

Some hoists have not had winches and have been difficult to use.

None of the earlier proposals were designed with an operators seat on an opposite side of an upper cable guide means from building-engaging wheels, as is important to position the operator out of a paint spray area and to space the operator from a building far enough for ease in handling work in front of him.

A long length of cable from a dangling scaffold to an upper anchoring point causes the tipping forces on a rearward side of a scaffold to tip the dangling scaffold to a dangerous and precarious extent.

As a scaffold moves upward, its effective cable portion is shorter, causing a different tipping angle, as has been a great problem whenever scaffolds are proposed having a center of gravity, of man and scaffold, which center is rearward of an upper cable guide. This problem, in my opinion, has kept such scaffolds from being more generally used.

SUMMARY OF THE INVENTION A scaffold suspended from a single cable and having an operator-supporting area substantially spaced rearwardly from its forward side, a cable guide means attached to an upper part of the frame of the scaffold and disposed a substantial and preferably adjustable distance from a forward side of the frame and toward a position above the position of the operator, whereby the downward force of the weight of the operator is partially counterbalanced, wheel means on the forward side of the frame and below the operators position for engaging the outer surface of a building so as to counteract the remainder of the downward force of the operator on the frame, the wheels being adjustably positionable greater and lesser distances to the right and left of the frame respectively, a winch assembly on the frame attaching the cable.

The means for attaching the cable guide means to the frame being quickly adjustable to a new setting by the operator while the operator is suspended on a scaffold in the air so as to correct the inclination of the seat which varies without such correction from a backwardly tilted position when there is a longer slack in the cable to a more forwardly tilted position when the scaffold is close to the upper anchoring point of the cable, whereby the seat can be maintained in a level position at all times.

The wheel-supporting assembly having horizontally forwardly extending portions on which storm windows or other objects can be rested and on which tools can be supported by various means whereby the scaffold can be effectively used by window washers, sand blasters, paint sprayers, brush painters, and workmen of many other kinds.

A particular object is to provide a single-cable scaffold which has stability of a sort ordinarily present in double-cable scaffolds only, since single cable devices of the prior art have been exceptionally dangerous.

The winch assembly having a foot-pedal-operated brake which can be quickly used for safety in an emergency while the operator's hands are occupied.

The wheels being adjustably connected to the frame in a manner for permitting them to be adjusted vertically with respect to the frame to assist in the adjustment of the balance of the scaffold so that the seat is level for a given load as is desirable in addition to the adjustment of the guide means while the scaffold is in the air.

The wheels being adjustable horizontally with respect to the frame so as to span window frames and other obstructions and so that one wheel can be adjusted inwardly when it is close to the edge of the building wall at the corner.

The winch being either a hand winch or a motor-driven winch, and in either case, the winch is mounted on the rearward of the upright frame member so as to be as far as possible from the forward wheels of the scaffold so that paint being sprayed cannot contaminate the working parts. The operator's seat position being at the rear of the scaffold so that he also is as far as possible from the paint being sprayed on a building. The motor being protected from spray by being placed behind the operators seat, and the winch being further protected by its placement beneath the operators seat.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a side elevation of the scaffold, a portion of a building wall being shown in engagement with the wheels thereof.

FIG. 1A is a side elevation of a modified upper portion of either of the scaffolds of FIGS. 1 and 2.

FIG. 2 is a side elevation of a modified scaffold for use with a hand winch, rearwardmost and forwardmost parts thereof being broken away.

FIG. 3 is a top plan view of the modified scaffold of FIG. 2.

FIG. 4 is a top plan view of the scafi'old of FIG. 1.

FIG. 5 is a top plan view of a central portion of the scaffold of FIG. I as modified by having an upper portion such as shown in FIG. 1A.

FIG. 6 is a frontal elevation of the scaffold of FIG. I with an upper central portion and one side portion broken away.

FIG. 7 is a frontal elevation of a central portion of the scaffold of FIG. 2 with an upper portion and side portions broken away.

DESCRIPTION OF THE PREFERRED EMBODIMENT The scaffold of this invention is generally indicated at 10 in FIG. I and comprises a frame generally indicated at 12 having a first frame portion 14 having a forward end 20 and a rearward end 22, the rearward end being horizontally spaced from the forward end, the frame portion 14 preferably being a single elongated steel structural member of extruded and economical form.

An operator-supporting seat is shown at 30 attached to the first frame portion 14 and disposed thereabove and having an upwardly facing operator-supporting surface means 34 for supporting the operator thereabove, the surface means being in a horizontal upper surface of the seat 30.

Frame 12 further has a second and upright frame portion 40, which latter is likewise preferably formed of an extruded steel structural member for economy, and more particularly, is preferably a tube, which latter is attached to the first frame portion 14 at the forward end 20 thereof rigidly.

A center 50 of the total area of the operator-supporting surface means 34, as seen in top plan view in FIG. 4, is disposed substantially spaced rearwardly from the forward side of the upright frame portion 14 whereby the weight of an operator thereon introduces a downward force tending to pry the upper end of the second and upright frame portion 40 rearwardly.

A cable 70 extends upwardly from the frame 12. A cable guide means generally indicated at 74 adjacent an upper part of the frame 12 and having a cable passage 76 therethrough from the bottom to the top thereof, as best seen in FIG. 1 at 76, is provided. A cable guide means attaching assembly generally indicated at 80 attaches the cable guide means 74 to the upper part of the upright frame portion 40.

A winch means generally indicated at 90 is mounted on the underside of the horizontal frame member 14 whereby it is in a position lower than the cable guide means 74.

The winch assembly 90 has the lower end of the cable 70 attached to it and an intermediate part of the cable 70 extends around the forward side of a pulley 96 which can be called an intermediate pulley 96 fastened to the frame 12 in a position forwardly of the seat 30 and adjacent the upright frame portion 40, thus making it possible for the cable 70 to be out of the way of the operator.

A pair of horizontally spaced wheels 100 are disposed forwardly of the second frame portion 40 and are adapted to rotate in substantially vertical planes extending forwardly and rearwardly in parallelism with each other so that the wheels are adapted to engage a vertical surface 102 of a building 110. The wheels 100 are attached to the frame by means ofa wheel attachment assembly generally indicated at 120. The cable guide means 80 can be in the form shown in FIG. 1 or in a form shown in FIG. 1A.

Referring to FIG. 1, a pair of pulleys 140 are shown spaced apart a slight distance forwardly and rearwardly at their pivot axis 142, the latter being attached to a top bar 154 having a plurality of openings therein horizontally spaced forwardly and rearwardly of the scaffold with respect to each other so that any one of them can be used to receive a bolt I60 for attachment to the upright frame portion 40.

A brace 170 is attached at its forward end to the bar 80 and extends downwardly andforwardly at an inclination to a bolt I74 which attaches it to the upright frame portion 40 by extending through a slot 180 extending vertically through the upright frame portion 40.

Referring to FIG. 1A, it will be seen that a cable guide means attaching assembly can also be made in the form shown there at 180 in which the upper bar 154 can be attached at its forward end by a bolt 184 to a plate 190 so that the bar 154 can swing upwardly and downwardly at its rearward end along the side of the vertical plate 190, whereby an attachment element 200 can be caused to extend through the bar 154 and to engage any one of a plurality of openings 210 arranged in an are about the center of the arc which is at the bolt 184, whereby the attachment element 200 can be placed through any one of the holes 210 to adjustably fix the cable guide pulley assembly 74 at any desired position closer or farther from the forward side of the scaffold and closer or farther from the center 50 of the area in which the operator is sitting.

Referring to FIG. 5, it will be seen that the bar 154 can be used in conjunction with another bar 240 parallel to it disposed on the opposite side of the pulleys 140 and secured by the same bolt 184 at one end and similarly attached to the pulleys. The connecting element 200 can be held in place by a chain 250 attached to the upright frame portion 40 and another chain 252 can secure a cotter pin 256 to the upright portion.

A horizontal handle 270 can extend to one side of and be attached to one of the bars 154 or 240 so that it can be reached by an operator for use in pulling the pulleys 140 into a different position when desired.

The adjustment of the position of the pulleys 140 nearer or farther from the center of gravity of the entire scaffold with the operator on it is an adjustment that can be made by the operator while he is suspended alongside the building. It is important that this be possible because the effective force on the scaffold of the suspending cable is so different when the scaffold is close to the upper anchoring point of the cable than it is farther therefrom.

The operator will find himself comfortable and able to move about well during his work with his back against the backrest portion 270 of the seat 30.

Referring to FIG. 1, it is to be understood that the winch assembly is one of a type having a winch drum about which the cable 70 is wound, having a brake for the winch drum, having an operating lever, not shown, to which the brake cable 290 is attached, these parts all being disposed in a first housing 292, with power for the winch drum supplied by a motor 294 mounted on the back of the seat 270'and forming a part of the winch assembly. The motor 294 is connected to the winch drum by any suitable means such as a cog wheel and chain assembly 296.

The brake cable 290 extends forwardly and downwardly from the seat area and attaches to the upper end of a brake foot pedal 300 which is hingedly secured at its lower end to a horizontally extending inner portion 310 of the wheel mounting assembly 120 earlier mentioned.

When the operator pushes the pedal 300 downwardly, the cable 290 operates the brake, not shown, of the winch assembly 90 in a manner conventional for winches, although the position of the pedal 300 is believed new in scaffolds.

Referring to FIG. 4, the wheel attachment assembly 120 can there be seen to have a central upright portion 400 which telescopes into the bottom of the hollow tubular upright frame portion 40, being positionable selectively therein because of vertically spaced openings 402 in the upright member 40 and in the central upright member 400. A bolt 412 extending through the opening in the upright frame member 40 and in the central upright member 400 attaches them together in vertical adjustment.

A transverse inner member 310 of the wheel attachment assembly 120 can be seen in FIG. 6 to extend to the right and left of and be attached to the lower end of the central upright portion 40th.

Referring to FIG. 4, it can there be seen that the central horizontal portion 310 is hollow and has openings therethrough as seen at 420 for cooperation with horizontally spaced openings 424 in a right and a left extension member 426 and 428, which latter telescope into the right and left ends of the tubular member 310 and are selectively and adjustably secured thereto by a bolt 450 on the right and another bolt 450 on the left,

Forwardly extending portions 460 of the wheel attachment assembly generally indicated at 120 are attached to the outer ends of the members 426 and 428 and extend horizontally forwardly therefrom equal distances and the wheels are attached to the forward ends thereof by the wheel axles 470.

In operation, it will be seen by this construction that the wheels 100 can be set at greater or lesser spacings with respect to the upright frame portion 40 for spanning windows or other obstructions on the sides of buildings which can vary in width. The two wheels 100 need not be spaced to the side of the upright frame portion 40 equal amounts, as might be desirable when working close to the corner ofa building wall at its edge.

The motor of the winch assembly 90 is controllable for winding, unwinding, and providing no power at all, by the shifting of a control lever 500, seen in FIG. I, to the operator's right, left, and center respectively. At the lower end of the control lever 500 is a switch assembly 510 which is understood to be wired to the motor 294 in a conventional manner of such switches, and therefore, not shown.

Referring to FIG. 2, a modification is there shown in which a hand winch assembly generally indicated at 600 is employed, the winch drum of which is hand-driven by a crank 6l0 which extends out of the right-hand side, or if desired, out of the lefthand side, of the housing 612 and is cranked about a horizontal axle 630 in two directions for winding and unwinding the cable 70. The hand winch has a brake lever 640 movably connected thereto for controlling its brake. The lever 640 is attached to a brake cable 644, which latter extends downwardly and forwardly to a brake foot pedal 660 to the top of which it is attached, the foot pedal 660 being hinged at its lower end in an identical manner to that described earlier with respect to the modification of FIG. 1.

In FIG. 2, the cable extends behind a single pulley shown in dotted lines at 670 and it is to be understood that such a construction is much inferior to the positioning of the cable guide pulleys 140 shown in FIG. 1A, as is the preferred adjustable construction.

FIG. 7 shows a handle 690 attached to the upright frame member 40 and extending horizontally outwardly therefrom in an opposite side to the crank handle 610 for gripping by the operator with his other hand from his crank handle hand.

The central horizontal portion 310 of the wheel attachment assembly 120 there shown receives thereon modified right and left extension members 426 and 428, which latter are each tubular so that they can slide on the portion 310' and be attached thereto in any one of many selected positions of adjustable nature for positioning the respective wheels 100 farther to the right or left of the center of the scaffold respectively at times when the bolts 450' are removed from respective openings 420 and 424' in the right and left extension members 426 and 428' and in the respective central horizontal portion 310 so that adjustment can be permitted. It is to be understood that the members 426 and 428 have longitudinally spaced openings 424' therein similar to the construction of FIG. 4 which are adapted to register with openings 420 which are spaced with respect to each other farther to the right and to the left respectively on the respective right and left ends of the modified central horizontal portion 310, whereby the bolts 450 can be inserted through and removed from the openings 420' and 424 respectively, just as in the modification of FIG. 4 earlier described.

The advantage of the construction of FIG. 6 is that the right and left extension members 426 and 428' are on the outside where they can be more easily reached from the operators seat.

In FIG. 5, the handle 270 is close enough to the seat 30 that an operator seated on the seat can manipulate the handle 270 for adjusting the position of the cable guide means 74.

Iclaim:

l. A scaffold comprising: a frame comprising first and second frame portions, said first frame portion having a forward end and a rearward end horizontally spaced from said forward end, operator-spporting means attached to said first frame portion and having upwardly facing operator-supporting surface means for supporting an operator thereabove, said frame further having a second and upright frame portion attached to said first frame portion, a center of the total area of said operator-supporting surface means as seen in top plan view being disposed substantially spaced rearwardly from the forward side of said upright frame portion whereby the weight of an operator thereon introduces a downward force tending to pry the upper end of said second and upright frame portion rearwardly, a cable extending upwardly from said frame, a cable guide means adjacent an upper part of said frame and having a cable passage therethrough from the bottom to the top thereof, means attaching said cable guide means to said frame so that the cable guide means is disposed with its passage spaced a substantial distance from said center of area, a winch means mounted on a part of said frame which is lower than said cable guide means, a pair of horizontally spaced wheels disposed forwardly of said second frame portion and adapted to rotate in substantially vertical planes extending forwardly and rearwardly with respect to said frame for engaging a vertical surface of a building, and means for attaching said wheels to said frame.

2. The combination of claim I in which said means attaching said cable guide means to said frame is adjustable for fixing said cable passage in any selected one of various positions nearer or farther from said center of total area.

3. The combination of claim I in which a seat is mounted on a rearward part of said frame, said seat having a horizontally disposed upper surface which defines said operator-supporting surface means, said scaffold having1open spaces beneath the forward end of said seat in which t e legs of an operator can be disposed while he is sitting on said seat with his legs extending downwardly therefrom.

4. The combination of claim 3 in which said winch has a movable brake lever means thereon, a foot pedal mounted on said means attaching said wheels to said frame and disposed in a position below and forwardly of said seat, means connecting said foot pedal to said brake lever, a movement of said foot pedal forwardly causing said brake lever to be operated for braking said winch to prevent said winch from releasing portions of said cable.

5. The combination of claim 3 in which said means connecting said wheels to said frame is adjustable for the spacing of said wheels into various selected positions at various spacings to the right and left sides of said frame so as to adjust said wheels to span windows and impediments on the surface of a building.

6. The combination of claim 2 in which said means attaching said cable guide means to said frame comprises a plate fixed to an upper part of said second frame portion and having a surface disposed in a vertical plane extending forwardly and rearwardly, an elongated bar means having a forward end pivotally attached to said plate and having a rearward end to which said cable guide means is attached, said bar means having a hole extending from left to right therethrough, said plate means having a plurality of holes extending from left to right therethrough and arranged in the configuration of a portion of a circle with its center at the point of pivoting of said forward end of said bar means, and a removable connector extendable through said intermediate hole in said bar means and extendable through a selected one of the arcuately arranged holes in said plate for fixing said bar means in various positions with respect to said plate so as to fix said cable guide means at various distances from said center of said total area of said operator-supporting surface means.

7. The combination of claim 6 in which a handle is attached to said bar means in a position adapted to be gripped by an operator for raising and lowering the rearward end of said bar means.

8. The combination of claim 7 in which a seat is mounted on a rearward part of said frame, said handle of said bar means being close enough to said seat that an operator of average size can reach said handle while sitting on said seat for operating said bar means to adjust the position of said cable guide means.

9. The combination of claim I in which said winch means is a hand winch having a control handle, said winch being mounted on a rearward side of said second frame portion forwardly of and above said center of said total area of said operator-supporting surface means.

10. The combination of claim 3 in which said winch means is a winch assembly having a winch drum mounted beneath said seat and in which an intermediate pulley means is attached to said frame forwardly of said seat, said cable means extending from said winch drum forwardly to said intermediate pulley means, around the forward side of the latter and upwardly through said cable guide means.

11. The combination of claim 3 in which said means connecting said wheels to said frame is adjustable by an operator of average male size while the operator is seated on said seat. 

1. A scaffold comprising: a frame comprising first and second frame portions, said first frame portion having a forward end and a rearward end horizontally spaced from said forward end, operator-supporting means attached to said first frame portion and having upwardly facing operator-supporting surface means for supporting an operator thereabove, said frame further having a second and upright frame portion attached to said first frame portion, a center of the total area of said operator-supporting surface means as seen in top plan view being disposed sUbstantially spaced rearwardly from the forward side of said upright frame portion whereby the weight of an operator thereon introduces a downward force tending to pry the upper end of said second and upright frame portion rearwardly, a cable extending upwardly from said frame, a cable guide means adjacent an upper part of said frame and having a cable passage therethrough from the bottom to the top thereof, means attaching said cable guide means to said frame so that the cable guide means is disposed with its passage spaced a substantial distance from said upright frame on the same side thereof as the said center of area, a winch means mounted on a part of said frame which is lower than said cable guide means, a pair of horizontally spaced wheels disposed forwardly of said second frame portion and adapted to rotate in substantially vertical planes extending forwardly and rearwardly with respect to said frame for engaging a vertical surface of a building, and means for attaching said wheels to said frame.
 2. The combination of claim 1 in which said means attaching said cable guide means to said frame is adjustable for fixing said cable passage in any selected one of various positions nearer or farther from said center of total area.
 3. The combination of claim 1 in which a seat is mounted on a rearward part of said frame, said seat having a horizontally disposed upper surface which defines said operator-supporting surface means, said scaffold having open spaces beneath the forward end of said seat in which the legs of an operator can be disposed while he is sitting on said seat with his legs extending downwardly therefrom.
 4. The combination of claim 3 in which said winch has a movable brake lever means thereon, a foot pedal mounted on said means attaching said wheels to said frame and disposed in a position below and forwardly of said seat, means connecting said foot pedal to said brake lever, a movement of said foot pedal forwardly causing said brake lever to be operated for braking said winch to prevent said winch from releasing portions of said cable.
 5. The combination of claim 3 in which said means connecting said wheels to said frame is adjustable for the spacing of said wheels into various selected positions at various spacings to the right and left sides of said frame so as to adjust said wheels to span windows and impediments on the surface of a building.
 6. The combination of claim 2 in which said means attaching said cable guide means to said frame comprises a plate fixed to an upper part of said second frame portion and having a surface disposed in a vertical plane extending forwardly and rearwardly, an elongated bar means having a forward end pivotally attached to said plate and having a rearward end to which said cable guide means is attached, said bar means having a hole extending from left to right therethrough, said plate means having a plurality of holes extending from left to right therethrough and arranged in the configuration of a portion of a circle with its center at the point of pivoting of said forward end of said bar means, and a removable connector extendable through said intermediate hole in said bar means and extendable through a selected one of the arcuately arranged holes in said plate for fixing said bar means in various positions with respect to said plate so as to fix said cable guide means at various distances from said center of said total area of said operator-supporting surface means.
 7. The combination of claim 6 in which a handle is attached to said bar means in a position adapted to be gripped by an operator for raising and lowering the rearward end of said bar means.
 8. The combination of claim 7 in which a seat is mounted on a rearward part of said frame, said handle of said bar means being close enough to said seat that an operator of average size can reach said handle while sitting on said seat for operating said bar means to adjust the position of said cable guide means.
 9. The combination of claim 1 in which saId winch means is a hand winch having a control handle, said winch being mounted on a rearward side of said second frame portion forwardly of and above said center of said total area of said operator-supporting surface means.
 10. The combination of claim 3 in which said winch means is a winch assembly having a winch drum mounted beneath said seat and in which an intermediate pulley means is attached to said frame forwardly of said seat, said cable means extending from said winch drum forwardly to said intermediate pulley means, around the forward side of the latter and upwardly through said cable guide means.
 11. The combination of claim 3 in which said means connecting said wheels to said frame is adjustable by an operator of average male size while the operator is seated on said seat. 